WO2016150409A1

WO2016150409A1 - Equipment for 3d printing

Info

Publication number: WO2016150409A1
Application number: PCT/CZ2016/050007
Authority: WO
Inventors: Jan HOLÍK
Original assignee: Holík Jan
Priority date: 2015-03-24
Filing date: 2016-03-07
Publication date: 2016-09-29
Also published as: EP3274157A1; CZ2015205A3

Abstract

Device with the possibility of simultaneous printing of more layers of objects (see the drawing 2) is equipped with the hoppers (17) for the application of the building powder (15) in individual layers on the printing area (18). Device with the possibility of simultaneous printing of more layers of objects which is equipped with the hoppers (17) for the application of the building powder (15) in individual layers on the printing area (18) and the printheads (4) with their systems of jets for the printing of 3D objects by the application of a binding agent or hardening beam on the building powder (15) in particular areas. Printing area (18) can be moved horizontally on the conveyor belt or vertically on the lifting table and that above this printing area (18) there is the conveyor (6) for printing placed in the adjustable angle (β) and there are individual hoppers (17) and printheads (4) placed behind them attached on this conveyor (6) and the hoppers (17) and even the printheads (4) are oriented transversely to the direction of movement of the conveyor (6) for printing and have an elongated shape.

Description

EQUIPMENT FOR 3D PRINTING

Field of technology

Invention relates to equipment for 3D printing of objects with extended range of movement in more axis.

Current status of technology

3D printing is a process during which a specific device creates three-dimensional objects from suitable material. Printing in layers is operated by the control electronic based on a program model.

Currently, the most frequent printers used for the printing of 3D objects are 3D printers which use different types of ABS plastics etc. as a building material. Those printers use one or more printheads which contain several jets which apply the building material on the basis of melted plastics in one layer on the trajectory defined by the machine according to a numerical program (NC, CNC). Melted material is becoming stiff during the printing and creates a solid shape.

Second type which is used mainly in industrial 3D printers is also using one printhead, but used technology can be different. Printhead for the application of a binding agent has thousands of jets. Those 3D printers work with a building powder from which a printed object Is created. This building powder can be based on ceramics, sand, metal etc. In order to create a solid state from this powder different types of bonding agents or hardening laser beams applied by a printhead during the printing on this building powder are used. Constructional disadvantage of current printers of this type is that when the building powder is applied the printhead is stationary which is slowing down the production. It is not possible to print when the building powder is being applied.

Common known 3D printers usually also have really limited working space which limits possible maximal size of created object. This is why the bigger pieces have to be printed in parts and then subsequently assembled into one piece. With regard to obvious disadvantages of such procedure there are efforts to remove or at least reduce those dimensional limits. Example of a partial solution of the mentioned problem can be the method and device for the creation of three-dimensional objects by 3D printing according to the German patent application DE102010015451. In this application the printed 3D object is created from the building powder which is delivered by a supply device in individual layers. Shape of the object is formed by a printhead stored on a cantilever frame under defined angle which allows 3D printing of objects with larger dimensions in comparison to current small devices. This is because one dimension is not limited by the size of a machine because the printed piece is taken away from the printhead by a conveyor to any area which is accessible for operators during full operation of the machine. In this case dimensions of the printed piece are limited by a width and height of the frame. This solution can accelerate the production because the operation of 3D printer does not have to be stopped because of the manipulation with a printed piece. However this construction of mentioned device for the 3D printing does not allow simultaneous movement for the application of the building powder and movement of the printhead which limits even faster production which can be sufficient, for example, for the mass production.

Substance of the invention

The device for 3D printing according to the invention contributes to the removal of above mentioned disadvantage, because its construction allows operation of all processes of 3D printing simultaneously and in more layers. Similarly to the above mentioned known device this device is equipped with a printing area which can be moved horizontally or vertically. Substance of the invention is that above this printing area there is the conveyor for printing which has adjustable angle. On this conveyor for printing there are individual hoppers for the application of the building powder in individual layers on the printing area which are oriented transversely to the direction of movement of the conveyor for printing and which have an elongated shape. Each hopper is followed by a printhead which has jets necessary for the 3D printing along its entire length.

Main contribution of the invention is that the conveyor for printing with printheads and hoppers and the conveyor belt of a printing area with printed piece or pieces are moving simultaneously during 3D printing. By the regulation of the speed of those movements and speed of the application of the building powder the thickness of applied layer and also the angle of a printing area can be adjusted.

The conveyor for printing can be created from an endless belt with a possibility of the cyclic rotation of hoppers and printheads attached to it during the printing.

In a different arrangement when the conveyor for printing is parallel to the printing area, i.e. angle β=0, the conveyor for printing can be created from a conveyor with an oscillating movement of hoppers and printheads from one side to other and without the cyclic rotation. In this case one printhead has two hoppers.

The device according to the invention has a dispenser of the building powder for individual printing systems placed above the conveyor for printing. This dispenser has a linear routing in order to move and to supply during the printing.

Data for the operation of a hopper and printhead can be sent using a data cable, but also the wireless Wi-Fi can be used.

The conveyor for printing can be equipped with a cleaning device for printheads.

The device for the printing of 3D objects according to the invention is advantageous especially because of its construction which allows continuous printing of more layers without a necessity to stop the device.

This device (if it is arranged in compliance with the invention) allows especially the acceleration of a production of 3D objects. This acceleration is achieved by its different constriction for printing, involvement of more hoppers which create individual layers from the building powder for printing and by involvement of more printheads which create a shape of the object. This change requires the hopper with a powder and the printhead to be placed consecutively. Connection of more hoppers and printheads allows that more layers can be printed during one cycle and this is the basis for mentioned acceleration in comparison to current solutions.

Technology of the acceleration of printing is further achieved by the construction principle when the hopper, printhead and printing area moving relative to each other at the same time. By the regulation of all movements during 3D printing the thickness and angle of applied layer of the building powder can be adjusted. When the printing is commenced the hopper moves together with the printhead and the hopper begins to spread the building powder on the printing area. At the same time the printing area is moving as well, because it is being moved by the conveyor belt or table. After some time when the area of this first print is gradually moved by the distance equal to the thickness of the layer which is necessary for other layer, the second hopper begins to spread the second layer. Each hopper -^i

and printhead is a couple which creates its one layer and print and they are moving at a particular distance after the previous couple. This couple has a linear routing which allows the auxiliary copying of the descending printing area. This is how several layers are created consecutively in the same time without the necessity to stop the device until required thickness of the printed object is reached.

3D printing itself is done by the application of the building powder in a thin layer on the printing area by the hopper and following injection of a binding agent or application of a laser on this powder by the printhead. Solid shapes are being formed in areas of the building powder where the binding agent is used. However, the building powder remains powdery in areas of the building powder where the binding agent is not used. During the printing of powders of metals the chemical binding agent is used and after its application this binding agent is hardened by a heater. Also during the printing from metals the lasers are being used - the printhead is emitting laser beams and they fuse the building powder at high temperature which creates a solid shape from it. In areas where such laser was not used the building powder remains powdery.

Printed object is surrounded by a powdery building powder which was not hardened by a binding agent or laser during the printing and its subsequent removal is done by the suction. Loose material which remains on the printed object even after such suction is removed, e.g. by the brushing.

Explanation of the drawings

Attached drawings should help with the further clarification of the substance of the invention:

Fig. 1 - example of the construction for the continuous multilayer printing of 3D objects with the angular arrangement and horizontal movement of the printing area,

Fig. 2 - functional diagram of the continual multilayer 3D printing,

Fig. 3 - detail of the arrangement of a hopper and printhead,

Fig. 4 - exemplary execution of the device for the continual multilayer printing of 3D objects with the parallel (horizontal) arrangement and vertical movement of the printing area,

Fig. 5 - exemplary execution of the device for the printing of 3D objects with the parallel (horizontal) arrangement without the rotation of hoppers and printheads, Fig. 6 - exemplary execution of hoppers and printheads for the printing of 3D objects with the parallel arrangement and the oscillating movement of hoppers and printheads.

Examples of the execution of the invention

Example 1

In the exemplary execution of the device for the continuous multilayer printing of 3D objects with the angular arrangement (see drawings 1 and 2) the printing area is 18 with applied building powder 1 movable on the conveyor belt 7 on the drawing 1 in the direction of the arrow marked on the drawing 2. Behind the wall 8 of the device above the printing area 18 (see drawing 2) the conveyor 6 for printing is angularly placed and its movement is done using a cogwheel 12 derived from the drive Π. of the conveyor for printing. On this conveyor 6 for printing there are hoppers 17 and printheads 4 attached in holds 3 and they are oriented transversely to the direction of movement of the conveyor 6 for printing. Hoppers 17 are applying the building powder 15 in individual layers 20 (see drawing 4) on the printing area 18 (drawing 2) and the printheads are releasing the binding agent on individual layers 20 by their 4 systems of jets (drawing 4) and this binding agent is drying. This is how the 3D object 19 (drawing 2) is created. On the drawing 3 there is the detail where the hopper 17 is applying the layer with the thickness 25 which is evened out by the compounder of a surface 27 and subsequently the printhead 4 applies the binding agent through its jets.

The principal of the application of more layers 20 is drawn on the drawing 4. During the application of layers 20 the table 21 is moving and it has the same function as the conveyor belt 7 on the drawing 1. When the table 21 beings to descend during the application of a layer the hopper 17 and the printhead 4 copy such descending of the table 21. Descending and ascending of the hopper Γ7 and printhead 4 in relation to the printing area 18 on the drawing 2 allows movement of the linear routing 26 (on the drawing 3) which is part of the printing conveyor 6 (drawing 2). Distance of the printhead 4 from the applied layer 25 is monitored by the sensor 24 (drawing 3). After the printing is done the hopper 17 and printhead 4 return using their linear routing 26 to their original locations.

By the regulation of speeds of all movements necessary for 3D printing and speed of the application of the building powder 15 by the hopper 7 the thickness of a layer 25 is adjusted (see the drawing 3) and the angle a (see the drawing 2). If the angle a is greater than the angle β movement of the linear routing 25 on the drawing 3 is limited. You can have same results if you lower the angle J3 in relation to the angle a (drawing 2). Under the angle J3 the conveyor 6 for printing is placed. Under certain conditions when the angle js greater than J3 movement of the linear routing 26 might not be used during the printing (see the drawing 3). Those appropriate conditions are adapted for the regulation of speed of the application of the building powder 15 by the hopper 17 and speed of the movement of the conveyor belt 7 or table 21 which is driving into the container 22 for printing.

Dispenser 10 on the drawing 1 is moving on its linear routing 1 attached on the holder 2. This dispenser 10 refills the building powder 15 to hoppers 17 (see the drawing 2) through the hopper blades 16 powered by the drive 9 of hopper blades.

Conveyor 6 for printing is also equipped with the cleaning device 13 of the printheads 4.

Binding agent for printing, operating data and electric energy for the printheads 4 and hoppers 17 is transferred through the energy chain 5 with the input 14- Binding agent for the printheads 4 is released through the inlet vent 23 on the drawing 3.

Example 2

On the drawing 5 there is another option of the device according to the invention— exemplary execution of the device for the multilayer printing of 3D objects with the parallel (horizontal) arrangement, i.e. with the conveyor 6 for the printing parallel to the printing area 18, angle β=0. In this case the conveyor 6 for printing consists of the conveyor with the oscillating movement of the hoppers 17 and printhead 3 from one side to the other. In comparison to the previous solutions on the drawing 4 this principle of the printing is different because the hoppers 14 and printheads 4 are not rotating cyclically, but they are only moving in the direction of marked arrows from one side to the other on the linear routing together with the dispenser 10.

In order to ensure that the printing will be possible on both sides there have to be two hoppers 17 in this arrangement and they have to be located on both sides of the printhead 4 (see the drawing 6). If the conveyor 6 for printing is moving to the right the hopper on the right side 7 of the printhead 4 is applying the layer 25 and after the surface is adjusted by the compounder 27 jets of this printhead apply the binding agent on the layer 25. Binding agent for the printhead 4 is released through the inlet vent 23. If the conveyor 6 for printing is moving to the left the hopper on the left side 17 is applying the layer 25. It does not matter if the conveyor 6 for printing is moving to the right or to the left, only one of two hoppers 17 is applying the layer 25 for one printhead 4. Distance of the printhead 4 from the layer 25 is monitored by the sensor 24 and the thickness of layer 25 is regulated by movement of the linear routing 26.

Industrial applicability

Solution according to the invention can be used especially in the mechanical engineering, civil engineering, health care. It can be used especially for the creation of complicated shapes and parts which cannot be created using the conventional methods - machining, injecting or casting from steel or plastic. However the multilayer 3D printing can be also used for the creation of ordinary shapes using the powdered building material which ensures required quality of any material after printing together with the binding agent or laser.

Claims

P A T E N T C L A I M S

L Equipment for 3D pri ting of objects with the possibility of simultaneous printing of more layers of objects which is equipped with the hoppers (17) for the application of the building powder (15) in individual layers on the printing area (18) and the printheads (4) with their systems of jets for the printing of 3D objects by the application of a binding agent or hardening beam on the building powder (15) in particular areas and for which is typical that the printing area (18) can be moved horizontally on the conveyor belt (7) or vertically on the lifting table (21) and that above this printing area (18) there is the conveyor (6) for printing placed in the adjustable angle (β) and there are individual hoppers (17) and printheads (4) which can be moved on the linear routing (26) placed behind them attached on this conveyor (6) and the hoppers (17) and even the printheads (4) are oriented transversely to the direction of movement of the conveyor (6) for printing and have an elongated shape.

2 The equipment according to the claim 1 is characterized by the fact that the conveyor (6) for printing consists of an endless belt with the possibility of a cyclic rotation of the hoppers (17) and printheads (4) attached to it during the printing.

3. The equipment according to the claim 1 is characterized by the fact that in the arrangement when the conveyor (6) for printing is parallel to the printing area (18), i.e. the angle β=0, the conveyor (6) for printing consists of the conveyor with the oscillating movement of the hoppers (17) and printheads (4) from one side to the other without the cyclic rotation and in this case one printhead (4) has two hoppers (17).

4. The equipment according to the claim 1 is characterized by the fact that above the conveyor (6) for printing there is placed the dispenser (10) for the supply of individual hoppers (17) by the building powder (15) through the hopper blades (16).

5. The equipment according to the claim 1 is characterized by the fact that the operating data from individual printheads (4) and hoppers (17) are transferred wirelessly.

6. The equipment according to the claim 1 is characterized by the fact that the conveyor (6) for printing is equipped with the cleaning device (13) of the printheads (4).